People of all ages receive musculoskeletal injuries when muscles of the foot, ankle, knee and hip do not respond appropriately or quickly enough to stop the motion of the body, or of a particular joint, to prevent injury. Injuries to the lower extremities, such as a foot, ankle, knee, or hip, are among the most common and costly in our society. For example, ankle sprains numbered in excess of 9 million in the U.S. in 2008 and accounted for approximately 20% of all sports injuries. This seemingly simple medical issue generates an estimated $9 billion in office visits, treatment and lost productivity annually in the United States. While this statistic applies to the United States, the problem of lost productivity due to such medical issues is a global problem as well.
Clinical evidence suggests that “functional mobilization,” or proprioceptive and reactive balance training generates better outcomes than the alternative treatment approaches, such as conventional physical therapy, immobilization and therapeutic ultrasound. Proprioception is defined as “the unconscious perception of movement and spatial orientation arising from stimuli within the body itself.” Reactive balance is a person's ability to respond to a perturbation or unexpected disturbance and maintain their balance. Proprioceptive and reactive balance training can increase a person's endurance, coordination, and proprioception of the foot, ankle, knee and hip muscles. This can be particularly valuable for high level athletes and the elderly who need to rehabilitate an injured joint or wish to prevent future injury. It also has the potential to reduce costs associated with occupational injuries.
Injury prevention via lower extremity proprioceptive and reactive balance training may save society hundreds of millions of dollars in treatment costs and lost productivity. The implications are even greater when one considers the full impact of preventing falls in populations at risk, such as the elderly. Furthermore, perturbation training can generate cost savings in rehabilitation. Proprioceptive training may accelerate return to work by 5 days and return to sports by 9 days. This could save the general U.S. workforce millions of dollars per year and have dramatic financial implications for highly paid professional athletes and performers who rely on their ability to move.
Currently available devices for proprioceptive training do not offer the necessary complexity of motion required for effective proprioceptive training. They typically provide only one type of movement (e.g., lateral or rotational). Furthermore, they do not effectively challenge the patient with the unexpected movement, or perturbation, that is so often the root cause of injury. Rather, the movement of these devices is generated by the patient or generated in a machine-driven, short, repeating pattern. See, e.g., U.S. Pat. No. 5,904,636.
For example, one such commercially available device is sold under the trade name “Biomechanical Ankle Platform System (BAPS).” The system includes a platform and a series of pivot balls that are attached to the bottom of the platform. In operation, the user selects one or more pivot balls to attach to the platform and then the user performs exercises on the platform. All movement of the device is, thus, generated by the user. See also, U.S. Pat. Nos. 4,653,748; and 7,621,861. Devices of this type do not address the need for the user to respond to unexpected motion or perturbation which, as noted above, is often the cause of injury. A number of patents disclose rotational devices including elastic handles for the user to pull for exercising the arms and providing a more rigorous workout. These devices suffer from the same disadvantage that the user controls the motion of the device. See, e.g., U.S. Pat. Nos. 3,593,994; 6,461,285; 4,787,630; 4,332,405; and 5,279,533.
Another disadvantage of several existing designs is that they include relatively bulky frames for the user to hold on to while performing the exercises. In this regard, see U.S. Pat. Nos. 4,305,579; 5,337,757; 5,695,439; and 7,621,861. A number of devices also are limited in their range of motion because they are designed to mimic a given activity, such as surfing, skiing, sail boarding and skateboarding. See, U.S. Pat. Nos. 5,904,636; 4,252,312; 4,436,513; 7,357,767; and U.S. Pat. No. D530,374.
Many physical therapists prefer lighter, less bulky frames and equipment, especially when they are required to move from location to location to visit patients. They prefer to move the equipment within their own workspace and also prefer to bring the equipment to the patient in some instances. It is important to many physical therapists to have the functionality of reactive balance training equipment in a portable, light weight and affordable device.
In view of the disadvantages of existing devices, a need exists for more effective proprioceptive training that provides complexity of movement and challenges the patient with unexpected movement. One such apparatus is described in United States Application Publication No. 2010/0285941 which is hereby incorporated by reference in its entirety.